Gift, souvenir or premium items are frequently printed with characters, logos or designs to make them more desirable. Many people greatly enjoy choosing designs, slogans or personalization, and having unique gifts made while they wait. The ready availability of computers and computer printers has also made production of personalized, one-of a-kind items and items designed on demand commonplace, particularly when the goods are made of paper. However, there is currently no fast economical way to produce individually designed items made of ceramic or ceramic tile.
Traditionally these items, such as a mug, are screen-printed. The image is allowed to dry, then placed in a furnace at 800° F. to 1200° F. to cure the image on the mug. This process is very time consuming and expensive, with limited flexibility. The process is not suitable for preparation of goods on demand. Labor involved in preparation of the screens and firing of the furnace make the process generally expensive, but especially for small quantities of goods, the cost becomes prohibitive.
As an alternative, ‘coated mugs’ of ceramic are used for digital printing and for creating items on demand. An uncoated mug may be spray coated or dip coated in a bath to impart a coating that is receptive to transfer of inks from a dye-sub or toner image. However, use of such technology requires investment in additional spray-coating equipment or baths for dipping such articles. Articles that need to be coated have to be made in advance so that the coating has time to dry or cure.
This method is also disadvantageous for the vendor who produces the decorative articles. The vendor must now stock both coated and uncoated goods. This is expensive, not only in terms of the inventory he must carry, but also in terms of storage or warehouse space in which the items are stocked.
Articles of glass or metal can be engraved on demand but such processes require very expensive, computer-controlled engraving equipment. This process is also relatively slow, taking 20 minutes or more to engrave several words. The technique does not reproduce color, a huge disadvantage when attempting to capture multi-color graphics.
Polymer coatings are known in the art as outer layers for credit or identification cards to protect the images contained on the card from wear and weather. In particular, it is known to coat a polyester film with a polymeric layer and adhesive, and then transfer the adhesive and polymeric layer to the card with heat and pressure. The polymeric layer is a clear, protective coating, allowing images contained on the substrate card to show through.
It is therefore an object of this invention to provide an improved process for transferring an image onto ceramic articles.
Another object of this invention is to provide an improved process for transferring an image onto articles that do not require any prior coating or treatment.
Still another object of this invention is to provide an improved and economical process for making low volume or short run articles.
Yet another object of this invention is to provide an improved process for making articles with graphics designed and applied on demand.